Modularity has proved to be used for describing an exceptional property of the subject under matter and also to introduce a quality which positions the object in a very unique category within the field of architecture.Commuting among multiple viewpoints inside the blurry atmosphere that involves the term, the investigation will focus specifically on clarifying the concept of modular systems in architecture and all the questions arising from it. More than venturing to redefine it, the research is merely centered on revising the term and the ideas attached, inquiring into its background and reviewing a group of cases to help decant the significance of this matter.